# How to locally run and test the KPI Value Writer micro-service

### Pre-requisets 
Ensure the following requirements are meet before executing the KPI Value Writer service>

1. The KPI Manger and KPI Value API services are running and Apache Kafka is running.

2. A Virtual enviornment exist with all the required packages listed in the ["requirements.in"](https://labs.etsi.org/rep/tfs/controller/-/blob/develop/src/kpi_value_writer/requirements.in) file installed sucessfully.

### Messages format templates
The ["messages"](https://labs.etsi.org/rep/tfs/controller/-/blob/develop/src/kpi_value_writer/tests/test_messages.py) python file contains the templates to create gRPC messages.

### Unit test file
The ["KPI Value API test"](https://labs.etsi.org/rep/tfs/controller/-/blob/develop/src/kpi_value_writer/tests/test_kpi_value_writer.py) python file enlist various tests conducted to validate functionality.

### Flow of execution
1. Call the `RunKafkaConsumer` method from the `KpiValueWriter` class to start consuming the `KPI Value` generated by the `KPI Value API` or `Telemetry`. For every valid `KPI Value` consumer from Kafka, it invokes the `PrometheusWriter` class to prepare and push the metric to the Promethues DB.